Commit 5f116351 authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

multi: make curl_multi_wait avoid malloc in the typical case 

When only a few additional file descriptors are used, avoid the malloc.

Closes #1377
parent 55f4abab

lib/multi.c

+14 −4
Original line number Original line Diff line number Diff line
@@ -974,6 +974,8 @@ CURLMcode curl_multi_fdset(struct Curl_multi *multi, 
  return CURLM_OK;

  return CURLM_OK;

}

}





#define NUM_POLLS_ON_STACK 10



CURLMcode curl_multi_wait(struct Curl_multi *multi,

CURLMcode curl_multi_wait(struct Curl_multi *multi,

                          struct curl_waitfd extra_fds[],

                          struct curl_waitfd extra_fds[],

                          unsigned int extra_nfds,

                          unsigned int extra_nfds,
@@ -987,8 +989,10 @@ CURLMcode curl_multi_wait(struct Curl_multi *multi, 
  unsigned int nfds = 0;

  unsigned int nfds = 0;

  unsigned int curlfds;

  unsigned int curlfds;

  struct pollfd *ufds = NULL;

  struct pollfd *ufds = NULL;

  bool ufds_malloc = FALSE;

  long timeout_internal;

  long timeout_internal;

  int retcode = 0;

  int retcode = 0;

  struct pollfd a_few_on_stack[NUM_POLLS_ON_STACK];





  if(!GOOD_MULTI_HANDLE(multi))

  if(!GOOD_MULTI_HANDLE(multi))

    return CURLM_BAD_HANDLE;

    return CURLM_BAD_HANDLE;
@@ -1028,9 +1032,14 @@ CURLMcode curl_multi_wait(struct Curl_multi *multi, 
  nfds += extra_nfds; /* add the externally provided ones */

  nfds += extra_nfds; /* add the externally provided ones */





  if(nfds || extra_nfds) {

  if(nfds || extra_nfds) {

    if(nfds > NUM_POLLS_ON_STACK) {

      ufds = malloc(nfds * sizeof(struct pollfd));

      ufds = malloc(nfds * sizeof(struct pollfd));

      if(!ufds)

      if(!ufds)

        return CURLM_OUT_OF_MEMORY;

        return CURLM_OUT_OF_MEMORY;

      ufds_malloc = TRUE;

    }

    else

      ufds = &a_few_on_stack[0];

  }

  }

  nfds = 0;

  nfds = 0;
@@ -1108,6 +1117,7 @@ CURLMcode curl_multi_wait(struct Curl_multi *multi, 
    }

    }

  }

  }





  if(ufds_malloc)

    free(ufds);

    free(ufds);

  if(ret)

  if(ret)

    *ret = retcode;

    *ret = retcode;